[0001] This invention relates to the production of ethoxylated alcohols by reacting said
alcohols with ethylene oxide. More particularly, this invention relates to the production
of ethoxylated alcohols by reacting said alcohols in the presence of a barium oxide
catalyst.
[0002] The general reaction of alcohols and ethylene oxide to form ethoxylated alcohols
or ethylene oxide adducts, has long been known and practiced on a commercial scale.
For example, these ethylene oxide adducts have been used as detergents and cleaning
agents, domestic and industrial laundry detergents, detergent builders, polishes,
sanitizers, and dry cleaning materials. Other users include the pulp and paper industry,
and the fiber industry. These materials are especially adapted to these uses since
they have functional properties such as wetting power, foaming, emulsifying and dispersing
abilities as well as solubliza- tion and detergent abilities to facilitate their use.
[0003] Much literature is available in the general area of ethoxylation of alcohols. Many
references are also available relating to the catalytic ability of various materials,
and the mechanism and kinetics of these reactions. For example, French Patent 1,365,945
teaches the use of compounds containing an active hydrogen atom reacted with ethylene
oxide in the presence of alkali metal base. Acidic catalysts in general are also known.
However, the ethoxylation of alcohols inevitably produces a distribution of various
adducts. For example, in surfactant applications an adduct with too few ethylene oxide
molecules is not effective because of poor solubility, while an adduct with too many
ethylene oxide molecules is likewise undesirable because of surface tension reduction
per unit mass decreases drastically with increasing molecular weight. Thus it has
long been essential to produce and use ethoxylates with as sharp a distribution in
the desired mole adduct range (5 to 10) as possible. Acid catalyzed reactions such
as that described above produce such ethoxylates, but these catalysts produce harmful
side products such as dioxanes which must be separated and removed prior to use.
[0004] Russian Patent 523,074 teaches that alkali metals and various carbonates can be used
to catalyze this reaction. The side product formation in these base catalyzed reactions
is very low, but in base catalyzed reactions the adduct distribution is undesirably
broad, such that a large proportion of the product obtained is not useful.
[0005] Representative of, but not exhaustive of, the art in this area is U.S. Patent 3,328,467
which describes the use of zeolites and modified zeolites as catalysts in ethoxylation
reactions. French 1,557,407 uses triethyloxonium fluoroborate to catalyze such reactions.
Indeed, the art abounds with references to alkali metal hydroxides, such as sodium
and potassium hydroxide, tertiary amines and sodium.metal. German Offengungsschrift
2,639,564 teaches polyalkylation of active hydrogen compounds in the presence of sodium
trifluoroborate or perchlorates of metals such as magnesium, calcium, manganese or
zinc. U.S. Patent 3,969,417 uses tertiary oxonium salts as a catalyst. However, all
these materials have the disadvantages described and set forth above.
[0006] It would therefore be of great benefit to provide a catalyst which provides the low
by-product levels of base catalysts, yet has the narrow distribution of the preferred
mole adducts obtained from acid catalysts. Such a catalyst, which would promote the
narrowing of the product distribution curve, would contribute significantly to the
intrinsic value of the ethoxylates produced.
[0007] It is therefore an object of the present invention to provide a catalyst which will
yield a narrow, high mole adduct distribution from the reaction of alcohols of all
classes with ethylene oxide while providing low levels of undesirable by-products
and unreacted free alcohols. Other objects will become apparent to those skilled in
this art as the description proceeds.
[0008] It has now been discovered according to the instant invention that ethoxylation of
all classes of alkanols can be carried out in the presence of barium oxide, hydrated
barium oxide, and other barium bases such as barium metal, providing a narrow distribution
at high mole ethylene oxide adducts while yielding a very low level of free alcohols
and undesirable by-products.
[0009] Thus, the instant invention describes a method for the ethoxylation of alcohols comprising
contacting said alcohol with ethylene oxide in the presence of barium oxide catalyst.
The instant invention is normally carried out at temperatures of from about 200°F
to about 500°F. Normally, the alcohols reacted under the process of the instant invention
will contain from about 4 to about 18 carbon atoms but alcohols containing from about
10 to about 16 carbon atoms are those most used for commercial purposes.
[0010] While the instant invention is effective with all classes of.alkanols, both primary,
secondary, tertiary, linear and branched, linear and branched primary alkanols are
the most commonly used alcohols and are the preferred alcohols of the instant invention.
Representative examples of such alcohols are those derived by hydrogenation of natural
fats and oils, such as CO and TA alcohols, trademark of and sold by Proctor and Gamble
Co., such as CO-1214N alcohol, CO 1618 alcohol, and TA 1618 alcohol, and ADOL alcohols,
trademark of and sold by Ashland Oil Co., such as ADOL 54 alcohol, ADOL 61 alcohol,
ADOL 64 alcohol, ADOL 60 alcohol, and ADOL 66 alcohol. Alcohols produced by Ziegler
chemistry can also be ethoxylated. Examples of these alcohols are ALFOL alcohols,
trademark of and sold by Continental Oil Co., such as ALFOL 1012 alcohol, ALFOL 1214
alcohol, ALFOL 1412 alcohol, ALFO
L 1618 alcohol, ALFOL 1620 alcohol; and EPAL alcohols, trademark of and sold by Ethyl
Chemical Co., such as EPAL 1012 alcohol, EPAL 1214 alcohol, EPAL 1418 alcohol. The
invention is extremely useful for oxo alcohols (hydroformylation) produced from olefins.
Examples of such alcohols are NEODOL alcohols, trademark of and sold by Shell Oil
Co., such as NEODOL 23 alcohol, NEODOL 25 alcohol, NEODOL 1418 alcohol; TERGITOL-L,
trademark of Union Carbide Corp, such as TERGITOL-L 125 alcohol; and isodecyl and
tridecyl alcohols, sold by Exxon Corp., such as isodecyl alcohol and tridecyl alcohol.
Guerbet alcohols can also be ethoxylated. Representative examples of these alcohols
are STAN
DAMUL alcohols, trademark of and sold by Henkel Chemical Co., such as STANDAMUL GT-12
alcohol, STANDAMUL GT - 16 alcohol, STANDAMUL GT-20 alcohol, STANDAMUL GT-1620 alcohol.
Secondary alcohols can also be used, such as TERGITOL 15 alcohol, trademark of and
sold by Union Carbide Corp.
[0011] Generally, useable alcohols include 1-decanol; 1-undecanol; 1-docecanol; 1-tricecanol;
1-tetradecanol; 1-pentadecanol; 1-hexadecanol; 1-heptadecanol; 1-octadecanol; 1-nonadecanol;
1-eicosanol; 1-dicosanol; 2-methyl-1-undecanol; 2-propyl-l-nonanol; 2-butyl-l-octanol;
2-methyl-1-tridecanol; 2-ethyl-l-dodecanol; 2-propyl-l-undecanol; 2-butyl-l-decanol;
2-pentyl-1-nonanol; 2-hexyl-l-octanol; 2-methyl-l-pentadecanol; 2-ethyl-l-tetradecanol;
2-propyl-l-tridecanol; 2-butyl-l-dodecanol; 2-pentyl-l-undecanol; 2-hexyl-l-decanol;
2-heptyl-1-decanol; 2-hexyl-1-nonanol; 2-octyl-l-octanol; 2-methyl-1-heptadecanol;
2-ethyl-l-hexadecanol; 2-propyl-1-pentadecanol; 2-butyl-1-tetradecanol; 2-pentyl-1-tridecanol;
2-hexyl-l-dodecanol; 2-octyl-1-decanol; 2-nonyl-1-nonanol; 2-dodecanol; 3-dodecanol;
4-dodecanol; 5-dodecanol; 6-dodecanol; 2-tetradecanol; 3-tetradecanol; 4-tetradecanol;
5-tetradecanol; 6-tetradecanol; 7-tetradecanol; 2-hexadecanol; 3-hexadecanol; 4-hexadecanol;
5-hexadecanol; 6-hexadecanol; 7-hexadecanol; 8-hexadecanol; 2-octadecanol; 3-octadecanol;
4-octadecanol; 5-octadecanol; 6-octadecanol; 7-octadecanol; 8-octadecanol; 9-octadecanol;
9-octadecen-1-ol; 2,4,6-trimethyl-1-heptanol; 2,4,6,8-tetramethyl-l-nonanol; 3,5,5-trimethyl-l-hexanol;
3,5,5,7,7-pentamethyl-1-octanol; 3-butyl-l-nonanol; 3-butyl-1-undecanol; 3-hexyl-l-undecanol;
3-hexyl-l-tridecanol; 3-octyl-l-tridecanol; 2-methyl-2-undecanol; 3-methyl-3-undecanol;
4-methyl-4-undecanol; 2-methyl-2-tridecanol; 3-methyl-3-tridecanol; 4-methyl-3-tridecanol;
4-methyl-4- tridecanol; 3-ethyl-3-decanol; 3-ethyl-3-dodecanol; 2,4, 6,8-tetramethyl-2-nonanol;
2-methyl-3-undecanol; 2-methyl-4-undecanol; 4-methyl-2-undecanol; 5-methyl-2-undecanol;
4-ethyl-2-decanol; 4-ethyl-3-decanol.
[0012] While pressure or lack of pressure is not a detriment to the process of the instant
invention, normally a pressure of up to about 100 pounds per square inch gauge (psig)
can be used. Preferred pressures would be from about 10 to about 50 psig. However,
it must be realized that the reaction can be carried out in a vacuum or at pressures
above 100 psig if desired. It is simply more convenient to carry out the reaction
in the pressure range of from about atmospheric to about 100 psig.
[0013] The instant invention is normally carried out at temperatures of from about 200 to
about 500°F. However, for practical reasons, commercial operations will normally be
carried out at temperatures in the range of from about 300 to about 400°F and the
most preferred temperature is around 350°F.
[0014] The reaction products of the described reaction can have any desired content of ethylene
oxide but will normally range from about 30 to about 80% content of ethylene oxide
(EO) based on weight. However, for most purposes the content of ethylene oxide will
range from about 40% to about 70%. The amount of EO present in the reaction is not
critical other than the minimum amount necessary to provide sufficient units to reach
the mole adduct level desired for the alcohol present. Excess EO does not affect the
reaction.
[0015] The barium oxide catalyst of the instant invention is a basic catalyst which provides
a sharp distribution as . to the mole adducts formed while reducing greatly the amount
of unreacted free alcohols and undesirable by-products normally found in sharp distribution
reactions. Barium oxide appears to be unique since tests carried out with metal oxides
of calcium and magnesium failed to reveal any significant ethoxylation capacity.
[0016] For the purposes of the instant invention barium oxide catalyst can be barium oxide
alone, barium metal, barium hydroxide, and barium hydroxide hydrates. Any of these
barium compounds are effective in the process of the instant invention. When used,
these catalysts can be used in any desired quantity. The larger the quantity used,
the more quickly the reaction goes to completion, although larger quantities do not
appear to significantly alter the distribution obtained. However, for practical reasons,
normally from about .01 to about .05 weight percent based upon the weight of the alcohol
to be reacted will be present in the reactor. However, it must be very clear that
these limits can be varied substantially since the catalyst is effective at all levels
and that catalyst concentration is simply a reaction rate modifier and not a reaction
distribution modifier.
[0017] Representative examples of such barium-containing catalysts are BaO, Ba(OH)
2 and Ba(OH)
2.XH
20 wherein X represents the number of water molecules present. X is not a critical
number.
[0018] Generally, treatment of alcohols with sthylene oxide yields a non-ionic detergent
since hydrogen bonding to the numerous oxygen atoms makes the polyether end of the
molecule water soluble. Alternatively, the ethoxylates can be converted into sulfates
and used in the form of sodium salts.
[0019] The instant invention thus provides the production of highly efficient alcohol ethoxylates
from primary, secondary, and tertiary branched chain and straight chain alkanols in
a novel, highly unexpected manner. The ethoxylate products normally have from about
4 to about 20 carbon atoms. The reaction products are useful as a nonionic surface
active agents with high wetting power which are composed of mixtures of monoalkyl
ethers of polyethylene glycol.
[0020] Thus in the preferred form of the instant invention, ethylene oxide is reacted with
a branched chain or straight chain higher alkanol in the presence of barium oxide,
barium hydroxide, or other barium bases.
[0021] The invention is more concretely described with reference to the examples below,
wherein all parts and percentages are by weight unless otherwise specified. The examples
are provided to illustrate the instant invention and not to limit it.
[0022] The ethoxylations were carried out in a stirred autoclave. Experimental conditions
are summarized in Table 1. Ethylene oxide (EO) was added as a liquid against a constant
nitrogen back pressure through a control valve. As the EO reacted with the alcohols
present, the pressure in the reactor was reduced, and additional EO was added through
the control valve until desired pressure was again obtained. Thus a constant pressure,
self-adjusting reaction took place. Figure 1 compares the distributions obtained from
barium oxide and sodium hydroxide catalyzed reactions. An examination of the figure
will show the extremely sharp distribution produced by barium oxide as compared to
sodium hydroxide.
![](https://data.epo.org/publication-server/image?imagePath=1980/02/DOC/EPNWA1/EP79100410NWA1/imgb0001)
Example 2
[0023] Table II summarizes experimental conditions used in the ethoxylation of 2-ethylhexanol-1.
Again reference is made to the reaction conditions of the table and to Figure 2 which
shows the very narrow distribution obtained with barium hydroxide as compared to sodium
hydroxide.
![](https://data.epo.org/publication-server/image?imagePath=1980/02/DOC/EPNWA1/EP79100410NWA1/imgb0002)
[0024] In the figures, the EO number was determined using well-known gas chromatographic
(GC) techniques.
Example 3
[0025] The base catalyzed ethoxylation of C
10 alcohols produced as straight chain primary alcohols of even carbon numbers under
a modified Ziegler-Natta polymerization of ethylene (sold as ALFOL 10 alcohols, trademark
of and produced by Continental Oil Company) was carried out under the reaction conditions
described in Table 3.
![](https://data.epo.org/publication-server/image?imagePath=1980/02/DOC/EPNWA1/EP79100410NWA1/imgb0003)
[0026] Relative weight percents of the ethylene oxide units adducted onto the alcohol are
shown in Table 4.
![](https://data.epo.org/publication-server/image?imagePath=1980/02/DOC/EPNWA1/EP79100410NWA1/imgb0004)
[0027] It has also been surprisingly discovered that the catalyst and method of the instant
invention is extremely well suited for ethoxylation of alcohols produced from olefins
by hydroformylation/hydrogenation. Such alcohols have in the past presented difficulty
when used as reactants for ethoxylation because of high concentration of unreacted
alcohols.
[0028] However, the catalysts of the instant invention produce an extremely good ethoxylate
using these products.
[0029] Thus it is apparent by practicing the instant invention high mole adducts, ethoxylates
of alcohols can be obtained in a very narrow, highly desirable distribution ranges
while producing very low amounts of by-products and unreacted free alcohols.
[0030] Gas chromatographic (GLC) analysis of the experiments described above showed the
basic barium-containing catalysts of the instant invention to be low in by-product
and unreacted free alcohols. A comparison with NaOH showed BaO to favorably compare
to the known basic catalyst. Both BaO and NaOH ethoxylation products contained less
than 1 part per million (ppan) dioxane and less than 3 weight percent polyethylene
glycohol (based on total reaction product, and determined by solvent extraction).
These basic catalysts produced reaction products far superior to those obtained in
acid catalyzed ethoxylations, in which reaction product dioxane normally exceeds 1000
ppm and polyethylene glycohol exceeds 3 weight percent.
[0031] The barium-containing catalysts of the instant invention excell in the low levels
of unreacted free alcohols in the reaction product. This superiority is clearly demonstrated
in Figures 1 and 2, where the relative amounts of unreacted alcohol are graphically
illustrated by referring to the locations of the respective graphs as they interset
the zero ethylene oxide number axis. The distance between the point of intersection
and the ordinate of the graph (0,0 value) indicates the free alcohols present. The
unreacted free alcohols present in BaO catalyzed reaction products is only about 30%
of that present in NaOH catalyzed reaction product.
[0032] Although exemplified as a batch reaction, the catalyst of the instant invention is
also extremely well- suited to continuous reaction methods since the reaction products
are of extremely desirable quality and quantity.
[0033] While certain embodiments and details have been shown for the purpose of illustrating
this invention, it will be apparent to those skilled in this art that various . changes
and modifications may be made herein without departing from the spirit or scope of
the invention.
1. A method for the ethoxylation of alcohols comprising contacting said alcohols with
ethylene oxide in the presence of a catalyst selected from the group consisting of
barium oxide, barium hydroxide, hydrated barium hydroxide or barium metal at a temperature
of from about 200°F to about 500°F.
2. A method as described in Claim 1 wherein the catalyst is selected from the group
consisting of barium oxide or hydrated barium hydroxide.
3. A method as described in Claim 2 wherein the alcohol contains from about 4 to about
20 carbon atoms.
-- 4. A method as described in Claim 3 wherein the alcohol is a primary alcohol.
5. A method as described in Claim 4 wherein the alcohol is a product of a hydroformylation/hydrogenation
reaction.
6. A method as described in Claim 5 wherein the reaction is carried out at a pressure
up to about 100 pounds per square inch gauge (psig).
7. A method as described in Claim 6 wherein the ethylene oxide mole adduct ranges
from about 30 weight percent to about 80 weight percent of the ethoxylated product.
8. A method as described in Claim 7 wherein the barium-containing catalyst is present
in an amount from about 0.1 to about 0.5% by weight based upon the alcohol to be reacted.
9. A method as described in Claim 2 when carried out as a continuous reaction.
10. A method as described in Claim 7 wherein the alcohol is a linear primary alcohol
containing from about 8 to about 16 carbon atoms, the ethylene oxide is present in
an amount of from about 40 to about 70 percent, temperature is from about 350°C, the
pressure is about 50 psig, and the barium-containing catalyst is present in a concentration
of from about 0.1 to about 0.5% based on the weight of the alcohol to be reacted.